Mark,



Thanks for answering my Ranco question below. It really helped. Now I have a couple more.....



Coil energized (below setpoint) - C connects to NO

Coil de-energized (at or above setpoint) - C connects to NC



So, for running my heat tape, I should have it wired to the NO contact, so that when the temp falls below the setpoint (- the differential), the NO contact will be closed and my tape will come on. Correct?



I actually had wired it the other way (to NC) and to make it work correctly, I had to set it to cool to make it turn the tape on when the temp reached a critical minimum. Now I understand why. Thanks.



Some power relays (relays for carrying a good amount of current) may have one contact heavier-rated than the other. A contact that stays closed can carry alot more current than one which is opened often, because there is an arc on an opening contact if the load is a motor (like an AC unit.) The Ranco may have a higher rated NO or NC contact for that reason, whichever one is used in Cool mode for an AC. I forgot which one you said it was.



So if I have it wired to the NO contact (which is rated at 16 full loaded amps and 15 resistive amps), I can safely use this unit for up to 1800 watts (15x120) of non-motorized heating equipment?



TIA for clearing this up for me.
-----
Chris Harrison



...he was beginning to realize he was the creature of a god that appreciated the discomfort of his worshippers - W. Somerset Maugham

[ Hide Replies ]

• Mark G., thanks for answers, and another Ranco question..... - chrish, Sun Dec 7 10:48:18 2003
• RE: Mark G., thanks for answers, and another Ranco question..... - markg, Sun Dec 7 20:28:23 2003
• Thanks again, Mark. /NP - chrish, Mon Dec 8 00:05:39 2003